Embraer EMB145 Operation Manual page 1674

The Windshear Escape Guidance Mode incorporates three control
sub-modes:
− Alpha Sub-mode - The airplane can be commanded to descend in
order to maintain airspeed when approaching stall conditions. If the
flight path angle control results in an angle of attack beyond the stick
shaker triggering angle, the windshear control law can keep the
airplane angle of attack below the stick shaker threshold.
− Gamma Sub-mode - The airplane can be prevented from
descending by commanding a positive flight path angle. A nominal
flight path angle is used to allow an airspeed raise during an
increasing performance windshear, in anticipation of a decreasing
performance windshear, and also to minimize altitude loss during a
decreasing performance windshear.
− Speed Target Sub-mode - The airplane is allowed to climb in order
to exchange excessive kinetic energy for potential energy. If the
control of the flight path angle results in an excessive speed
increase, the windshear control law maintains the airplane indicated
airspeed at the target speed.
The Windshear Escape Guidance mode will be canceled if any of the
following conditions occur:
− FLC, VS, SPD or ALT Mode is selected;
− Invalid AHRS data;
− Invalid ADC data;
− Invalid Stall Protection Computer (SPC);
− Radio Altitude greater than 1500 ft.
REVISION 39
AIRPLANE
OPERATIONS
MANUAL
CREW
AWARENESS
Page
2-04-35 7
Code
01